Figure 12.—Split boards. In actual work the back-lining would cover the entire back.
SPLIT BOARDS
While the old method of lacing-in is not desirable in library binding, the method of using split boards makes a very strong book. Instead of making a case of cloth, or cloth and leather, the back lining and the bands (or tapes) are inserted in boards which have been split, or between two thin boards glued together with a space left unglued for this purpose. The covering material is put on after the book is in boards and the book is made tight backed. This is probably the strongest method of attaching a book to the boards. In fact it is stronger than is necessary for any except very heavy books which receive hard wear. (Fig. 12.)
TIGHT AND LOOSE BACKS
For years there has been a certain mild controversy regarding the relative merits of tight and loose backs for leather bound books. Tight backs are those in which the material used for covering the book is pasted or glued to the back. Loose backs are those which, by means of folded paper or a piece of paper put in as described on page 37, are prevented from adhering to the back. When the book is opened the back springs out. (Fig. 13.)
The tight back book always forms a hinge at the place where the book is opened. Since the place of the hinge is constantly changing the back of the book after much use becomes concave instead of convex, and the appearance of the book is seriously marred. Also the constant creasing of the back tends to erase the gold lettering, so that it becomes indistinct. If labels are put on they speedily come off. It is customary to use tight backs on very heavy books, though there are cases where such books have been put in loose backs.
Figure 13.—Tight back and loose back.
The loose-back book always preserves its shape and good appearance, even when the paper on the inside may be so badly worn that the book should be withdrawn. The strain, however, always comes at the joint; therefore if poor leather is used it will quickly wear out at this point.